When I receive emails with attachments from people who use certain versions of Outlook, sent to my Yahoo account and received by Thunderbird using IMAP the emails have multipart attachments that are entirely unnecessary. They contain in every case (in addition to the attachment itself) a Winmail.dat file, a body_part_0.txt file, a body_part_1.rtf or .html file, a body_part_2.vcf file and a body_part_3.txt file. The very same email sent to my gmail or godaddy account is received with no such baggage. What is the issue between Thunderbird and Yahoo IMAP that causes this problem and how can I fix it? Charlie